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   PR # 42189
   Cluster mergers are thought to drive the X-ray evolution of clusters,
   but to fully understand these events we need to study young mergers.
   Classical signatures of a merger can last for up to 10$^9$ yrs. Radio
   halos, which are thought to be short lived (<10$^8$ yrs), are now
   thought to be powered by mergers. This makes these halos ideal
   indicators of a young merger. Furthermore, irregular radio halos are
   thought to be much younger than symmetric halos. The clusters with
   irregular radio halos and high quality X-ray data (A2256 & A754) have
   had anomalously hot gas (kT >> 8.5 keV) detected in them. We propose
   to obtain ASCA data for the recent-merger candidate A2255, a cluster
   with an irregular radio halo and evidence from the PSPC data of an
   anomalously hot component.
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